Pfizer-Drug Xalkori Approved for Lung Cancer, but at What Cost?

A new study has found that many people continue to smoke after being diagnosed with cancer. Photo: Reuters

New York City-based Pfizer Inc. gained FDA approval for their drug Xalkori, the first new medicine in several years for deadly, advanced lung cancer, according to new research.

Xalkori is used to treat certain patients with late-stage -- advanced or metastatic -- lung cancer along with an abnormal anaplastic lymphoma kinase (ALK) gene, which causes cancer development and growth.

The drug, which works by blocking certain proteins called kinases, including the protein produced by gene abnormality, is being approved with a companion diagnostic test from Abbott Molecular Oncology that helped determine if a patient has the gene.

“The approval of Xalkori with a specific test allows the selection of patients who are more likely to respond to the drug,” said Richard Pazdur, M.D., director of the Office of Oncology Drug Products in the FDA’s Center for Drug Evaluation and Research. “Targeted therapies such as Xalkori are important options for treating patients with this disease and may ultimately result in fewer side effects.”

The Wall Street Journal reports that, four years ago, Pfizer Inc. was on the verge of abandoning a cancer therapy until scientists discovered its effectiveness for, at the time, only a small group of people -- 6,000 patients a year in the U.S.

The results may not achieve multi-billion-dollar sales, but whether that yields a product for tens of millions of patients or 10,000 patients, we're interested, Geno Germano, who runs Pfizer's specialty-care and cancer businesses, told WSJ.

In two clinical trials involving about 255 patients, Xalkori delayed tumor progression for at least ten months in slightly more than half the patients who had a specific genetic mutation, the study noted.

Roughly one to seven percent of those with larger-celled lung cancer have the ALK gene abnormality, according to the FDA. Patients with this form of lung cancer are typically non-smokers.

Federal health regulators discussed the drug shortly after its U.S. approval based on it being reasonably likely to predict a clinical benefit to [lung cancer] patients, they said.

Xalkori is approved for the roughly four percent of patients with non-small cell lung cancer who have the gene.

In one study, the objective response rate was 50 percent with a median response duration of 42 weeks. In another, the objective response rate was 61 percent with a median response duration of 48 weeks with most patients tested had tumors shrink or disappear for months, without the nasty side effects of chemotherapy..

FDA officials said the most common side effects reported in patients receiving Xalkori included vision disorders, nausea, diarrhea, vomiting, swelling, and constipation.